by Gayle Garman
The pied-billed grebe is the smallest water bird at Green Lake; 13 inches long versus 23 inches for the more common mallard. Pied-billed grebes can be identified by their downy white butt and lack of typical tail feathers. Mature adults have a pale beak with a dark vertical stripe.
Several grebe pairs have nested on the Lake in past summers, but none have nested on Green Lake for the last 4 or 5 years. The cause or causes of their departure are not known but is probably related to increased activity on and around Green Lake and the loss of screening shoreline vegetation. The male and female both collect decaying aquatic vegetation to build the floating nest, which is surrounded by water for protection from rats, cats, racoons, dogs, and fisherman on the shore. Usually the nest is hidden in a near-shore willow thicket, or under overhanging vegetation.
The adults take turns incubating the eggs, which they cover with vegetation when they are both off the nest. There usually are 3-5 eggs, incubated for about 23 to 27 days (Birds of Washington State, Brian H. Bell and Gregory Kennedy, 2006). The chicks swim soon after hatching. They are lured into the water by the adults offering a small fish, their favorite food. A few days after hatching the chicks will spend most of the day on the water, being fed by both parents, but will return to the nest at night for a week or longer.
Grebes are truly aquatic birds that catch their food by rapid, agile swimming underwater, propelled by feet which are set far back on their body. In fact, they can hardly stand, and never walk on land, because their feet are so far back on their body that they cannot stay upright. They can control their buoyancy by compressing their feathers, so may be seen swimming with only their head above water, or slowly sinking beneath the surface without leaving even a ripple. Sometimes the chicks will ride on the back of an adult, even as the adult swims underwater. Like all grebes, they eat their own feathers, and the adults feed feathers to the young, to help rid their digestive tract of fish bones. Many pied-billed grebes stay at Green Lake over the winter because the lake provides good shelter, lots of small fish for food, and seldom freezes.
The pied-billed grebe is the most widely distributed grebe in the New World, and is found on marshes, ponds, small lakes and estuaries all over north America, however, populations are reported to be declining because of loss of habitat (Lives of North American Birds, Kenn Kaufman, 1996).
Photographs ©Gayle Garman